采用光学显微镜、扫描电镜、能谱仪和拉伸试验机等研究了6061-T6铝合金热轧厚板的显微组织及与轧制方向成0°,45°,90°方向的拉伸性能,并重点研究了合金的形变硬化特性.结果表明:6061-T6热轧厚板的晶粒沿热轧方向被拉长,脱溶平衡相(Mg2Si)和金属间化合物保留了轧制态特征;不同方向拉伸试样的拉伸性能和应变硬化指数存在取向性差异,但差异不大;不同方向拉伸试样的硬化曲线均呈幂乘抛物线形,存在取向性差异,在均匀塑性变形过程中形变硬化能力随着应变的增加而增大.

Optical microscopy,scanning electron microscopy,energy spectrum analysis and tensile testing were used to study the microstructure of 6061-T6 aluminum alloy hot-rolled plate and its tensile properties along the rolling direction in 0°,45°,90°.On these basis,the focus was on the strain hardening characteristics of the alloy.The results show that all grains are elongated along the hot-rolling direction,off the equilibrium phase (Mg2Si) and intermetallic compounds keep the characteristics of rolling state.The tensile properties and the strain hardening exponent of the tensile samples along different directions have difference in orientation,but the difference is small.The hardening curves of the tensile samples along different directions all exhibit exponentiation parabola and difference in orientation,and the strain hardening ability during uniform plastic deformation process increase with the increase of the strain.